This document provides definitions, guidelines and supportive information for the key performance parameters and their characterization methods of absorption liquids used in post-combustion CO2 capture. It covers common methodologies to measure and calculate specific key performance parameters of the absorption liquids.

The absorption liquids for post-combustion CO2 capture covered by this document are chemically reactive liquids, such as amine solutions, potassium carbonate solutions, aqueous ammonia, amino-acid salt solutions and mixtures of these reactants. Other absorption liquids based on different principles for CO2 capture are not covered.

The key performance parameters considered in this document relate to the design and operation of absorption liquid-based post-combustion CO2 capture processes, as well as equipment such as absorber and desorber columns, reboilers and other heat exchangers.

The key performance parameters are:

—     primary parameters, such as rich and lean CO2 loading, absorbent concentration, absorption capacity, heat of absorption, absorption rate and absorbent volatility;

—     secondary parameters, such as cyclic loading, that are directly derived from the primary parameters, or combined with other physical measurements, as in the case for the absorbent loss rate.

In addition, physical and chemical properties such as density, viscosity, pH, thermal conductivity and specific heat capacity are described. These properties are essential for understanding the key performance parameters of the absorption liquids.

This document also:

—     establishes key performance parameters (see Clause 4), physical and chemical properties of absorption liquids, and their calculation methods, and provides a common way of reporting them;

—     specifies the general requirements for the absorption liquid characterization in laboratory measurement and field testing (see Clause 5);

—     provides the requirements for the instrumentation to be installed or used, and guidelines for the characterization methods (see Clause 6);

—     provides information on the characterization methods of absorption liquids, describing all stages of test preparation, set-up and execution (see Annexes A to I), as well as guidance on sampling absorption liquids.

NOTE            While key performance parameters of absorption liquids are important process indicators for post-combustion CO2 capture, factors such as process design, equipment design and manufacturing, economics and safety are also considered for a comprehensive evaluation of post-combustion CO2 capture technology.

The document does not provide guidelines for benchmarking or comparing absorption liquids for post-combustion capture processes, nor does it offer methods to assess different technologies or projects, or specify methodologies for process engineering design. Additionally, the document is not intended to compel technology owners to disclose any intellectual properties related to their proprietary absorption liquids.

The document does not cover all available and emerging characterization methods for the key performance parameters considered in this document.